The present invention is directed to supporting tables or platforms particularly adapted to support a patient or the like in recumbent position and in which supporting leg mechanism is incorporated to allow the supporting table or platform to squat to a lowered position upon which a person, particularly a handicapped person seated in a wheelchair, may easily position himself or be positioned and thereafter be elevated to a position for treatment, examination or the like.
Typically, the supporting table may squat to a position in which the supporting surface thereof is elevated not more than about a foot above the floor or other like base surface, and is thereafter capable of being elevated to a maximum height of, say, thirty six inches above the floor. This capability allows substantial ease, comfort and safety in accommodating the person with whom the table is to be used. For example, the table may initially be adjusted in height to whatever lowered elevation is easiest, safest and most comfortable for transfer of the person to a supported position upon the table. Then, the person while recumbent or in the desired position may readily be elevated to that position required. The leg structure and raising/lowering mechanism provides an extremely steady and firm support in any position of the table even if the table is unevenly loaded as by a person sitting at one side thereof, is resistant to tipping or overturning in any vertical position, and is free from extraneous movements while being raised or lowered.
A beneficial feature of the invention is the capability for allowing the table to squat to an extremely low postion when this is necessary or desirable without any interference or contact with the underlying surface. Thus, the drive mechanism for operating the table vertically is compactly mounted beneath the table or platform and, as well, the supporting leg structures are widely stanced and fully supportive in any vertical position of the platform. Further, the feet for the supporting legs are disposed in fixed postions relative to each other and remain so while vertical adjustments are being made. Moreover, the individual leg structures at their attachment points to the table partake of smooth, coordinated and uniform movements during raising and lowering operations.
An important aspect of the invention resides in the utilization of an H-shaped main frame assembly underlying the platform and which serves not only to support and attach to the platform or table but also serves to mount the four supporting leg structures and the associated drive mechanisms in suspended relation thereto. The drive mechanisms incorporate lead-screw/nut drive assemblies which positively and firmly retain the platform in any elevated position thereof without danger of inadvertent downward movement. The uniform and coordinated movements of the leg structures, at the same time, assure that the platform is raised or lowered in level, steady fashion. Movable portions of the leg structures not only straddle opposite corresponding sides of the H-shaped main frame but also those associated portions of the lead-screw/nut drive mechanisms suspended thereon, thus contributing to the ability of the assembly to squat to an extreme lowered position. The cross piece of the main frame serves to mount and suspend not only a driving motor but also a suitable drive reduction unit in compact, effective fashion so that the squat position leaves sufficient clearance space beneath these units. This arrangement also allows a chain drive to be utilized from the reduction unit to the lead-screw/nut final drive units so that a smooth, noisless and effective drive arrangement is provided.
Other and further objects and advantages of this invention will become apparanent as this description proceeds.